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Evolution of quark-gluon plasma (QGP) near equilibrium can be described by the second-order relativistic viscous hydrodynamic equations. Consistent and analytically verifiable numerical solutions are critical for phenomenological studies of…

High Energy Physics - Phenomenology · Physics 2015-05-06 Long-Gang Pang , Yoshitaka Hatta , Xin-Nian Wang , Bo-Wen Xiao

We describe a general framework for avoiding spurious eigenvalues -- unphysical unstable eigenvalues that often occur in hydrodynamic stability problems. In two example problems, we show that when system stability is analyzed numerically…

Computational Physics · Physics 2008-12-01 M. Lisa Manning , B. Bamieh , J. M. Carlson

In this work we will treat the spurious eigenvalues obstacle that appears in the computation of the radial Dirac eigenvalue problem using numerical methods. The treatment of the spurious solution is based on applying Petrov-Galerkin finite…

Numerical Analysis · Mathematics 2017-09-14 Hasan Almanasreh

We introduce a family of discontinuous Galerkin methods to approximate the eigenvalues and eigenfunctions of a Stokes-Brinkman type of problem based in the interior penalty strategy. Under the standard assumptions on the meshes and a…

Numerical Analysis · Mathematics 2025-07-17 Felipe Lepe , Gonzalo Rivera , Jesus Vellojin

We have developed the formalism necessary to employ the discontinuous-Galerkin approach in general-relativistic hydrodynamics. The formalism is firstly presented in a general 4-dimensional setting and then specialized to the case of…

General Relativity and Quantum Cosmology · Physics 2011-08-08 David Radice , Luciano Rezzolla

Discontinuous Galerkin (DG) methods coupled to WENO algorithms allow high order convergence for smooth problems and for the simulation of discontinuities and shocks. In this work, we investigate WENO-DG algorithms in the context of…

General Relativity and Quantum Cosmology · Physics 2016-10-12 Marcus Bugner , Tim Dietrich , Sebastiano Bernuzzi , Andreas Weyhausen , Bernd Bruegmann

We apply the nested algebraic Bethe ansatz method to solve the eigenvalue problem for the SU(4) extension of the Hubbard model. The Hamiltonian is equivalent to the SU(4) graded permutation operator. The graded Yang-Baxter equation and the…

Strongly Correlated Electrons · Physics 2009-10-31 Heng Fan , Miki Wadati

A hybridized discontinuous Galerkin method is proposed for solving 2D fractional convection-diffusion equations containing derivatives of fractional order in space on a finite domain. The Riemann-Liouville derivative is used for the spatial…

Numerical Analysis · Mathematics 2016-07-12 Shuqin Wang , Jinyun Yuan , Weihua Deng , Yujiang Wu

By now Bayesian methods are routinely used in practice for solving inverse problems. In inverse problems the parameter or signal of interest is observed only indirectly, as an image of a given map, and the observations are typically further…

Statistics Theory · Mathematics 2023-11-02 Thibault Randrianarisoa , Botond Szabo

We present a novel class of locally conservative, entropy stable and well-balanced discontinuous Galerkin (DG) methods for the nonlinear shallow water equation with a non-flat bottom topography. The major novelty of our work is the use of…

Numerical Analysis · Mathematics 2022-02-01 Guosheng Fu

The work reported in this article presents a high-order, stable, and efficient Gegenbauer pseudospectral method to solve numerically a wide variety of mathematical models. The proposed numerical scheme exploits the stability and the…

Numerical Analysis · Mathematics 2023-03-06 Kareem T. Elgindy

We apply $hp$-cloud method to the radial Dirac eigenvalue problem. The difficulty of occurrence of spurious eigenvalues among the genuine ones in the computation is resolved. The method of treatment is based on assuming $hp$-cloud…

Mathematical Physics · Physics 2013-04-08 Hasan Almanasreh

Pseudodifferential operators of several variables are formal Laurent series in the formal inverses of $\partial_1, ..., \partial_n$ with $\partial_i = d$ $1 \leq i \leq n$. As in the single variable case, Lax equations can be constructed…

Mathematical Physics · Physics 2007-05-23 Min Ho Lee

The segmented formulation of the Tau method is used to numerically solve the non-autonomous forward-backward functional differential equation x'(t) = a(t)x(t) + b(t)x(t-1) + c(t)x(t+1), where x is the unknown function, a, b, and c are known…

Numerical Analysis · Mathematics 2016-08-05 Carmen Da Silva , René Escalante

In this paper, we present a Galerkin method for Abel-type integral equation with a general class of kernel. Stability and quasi-optimal convergence estimates are derived in ractional-order Sobolev norms. The fully-discrete Galerkin method…

Numerical Analysis · Mathematics 2018-03-08 Urs Vögeli , Khadijeh Nedaiasl , Stefan A. Sauter

Entropy stable methods have become increasingly popular in the field of computational fluid dynamics. They often work by satisfying some form of a discrete entropy inequality: a discrete form of the 2nd law of thermodynamics. Schemes which…

Numerical Analysis · Mathematics 2025-09-08 Brian Christner , Jesse Chan

We extend Petkov\v{s}ek's algorithm for computing hypergeometric solutions of scalar difference equations to the case of difference systems $\tau(Y) = M Y$, with $M \in {\rm GL}_n(C(x))$, where $\tau$ is the shift operator. Hypergeometric…

Symbolic Computation · Computer Science 2025-03-26 Moulay Barkatou , Mark van Hoeij , Johannes Middeke , Yi Zhou

Using the original advanced version of the direct method, we efficiently compute the equivalence groupoids and equivalence groups of two peculiar classes of Kolmogorov backward equations with power diffusivity and solve the problems of…

Mathematical Physics · Physics 2025-09-18 Serhii D. Koval , Elsa Dos Santos Cardoso-Bihlo , Roman O. Popovych

The high-order numerical solution of the non-linear shallow water equations (and of hyperbolic systems in general) is susceptible to unphysical Gibbs oscillations that form in the proximity of strong gradients. The solution to this problem…

Numerical Analysis · Mathematics 2016-07-18 Simone Marras , Michal A. Kopera , Emil M. Constantinescu , Jenny Suckale , Francis X. Giraldo

We establish a Schauder-type estimate for general local and non-local linear parabolic system $$\partial_tu+\mathbf{L}_su=\Lambda^\gamma f+g$$ in $(0,\infty)\times\mathbb{R}^d$ where $\Lambda=(-\Delta)^{\frac{1}{2}}$, $0<\gamma\leq s$,…

Analysis of PDEs · Mathematics 2024-07-09 Ke Chen , Ruilin Hu , Quoc-Hung Nguyen